It is known that infection is spread via skin contact through the transmission of pathogenic microorganisms. Hitherto, in order to reduce the presence of such organisms it has been known to scrub the skin with a solution containing a surfactant followed by application of an antiseptic.
In recent years it has been suggested that it would be desirable to combine the washing and disinfectant actions in a single operation by providing a composition comprising both an antimicrobial agent and a surfactant. It has been found however that many antimicrobial agents such as chlorhexidine [N,N′-bis(4-chlorophenyl)-3,12-diimino 2,4,11,13-tetraazatetradecanediimidamide] digluconate and other chlorhexidine salts are incompatible with anionic surfactants, and are reduced in their antimicrobial activity by nonionic surfactants, thus requiring addition of more antimicrobial agent in order to retain sufficient biocidal activity at the amount of surfactant required for satisfactory foam formation.
In particular, U.S. Pat. No. 3,855,140 assigned to Imperial Chemical Industries describes a skin cleansing composition comprising a soluble salt of chlorhexidine in combination with a polyoxyethylenepolyoxypropylene block copolymer. In order to obtain sufficient sudsing of the polymer it is necessary to use high proportions of the surfactant in amounts of the order of 20–25%. High amounts of chlorhexidine are consequently required to maintain the desired antimicrobial activity. Such high amounts are undesirable as it is known that surfactants may affect the skin adversely by defatting, and causing, when in combination with biocides such as chlorhexidine, irritation to the skin. Further the ingredients of the composition can be costly.
It would be desirable therefore to provide a composition in which the amount of antimicrobial agent and surfactant is reduced whilst maintaining sufficient antimicrobial activity and sudsing ability.
In this regard, in order to provide such a composition, WO 95/09605 teaches one to combine a phenolic disinfectant with an alkylpolyglucoside surfactant. As indicated in that patent however, such compositions, although showing good biocidal activity against most microorganisms, are incapable of disinfecting surfaces contaminated by the microorganism Pseudomonas aeruginosa to which the compositions are inactive.
It is an object of the invention to substantially ameliorate the disadvantages of the prior art.